The overall goal of this proposal is to determine the means by which the corneal epithelium interacts with the extracellular matrix (ECM) and thus, gain a better understanding of adhesion disorders and mechanisms of healing of ocular surface wounds. My working hypothesis is that there are multiple, specific cell surface binding sites or receptors on the basal epithelial cell surfaces that serve to link the epithelium via cytoskeleton or other relays to the ECM. ECM binding sites are responsible for adhesion and stabilization of the cytoarchitecture of the quiescent epithelium; upon lesion of the corneal epithelium, these ECM binding sites become dynamically involved in the process of epithelial migration and subsequent restoration of a normal corneal surface. Study of epithelial ECM binding sites under two different physiological conditions of the epithelium, quiescent and migratory, will provide valuable new information pertaining to the cell biological functions of ECM receptors in epithelial adhesion, mechanical stability of the epithelium-stroma interface, and wound healing of corneal epithelium. To reach this goal, we will use a combination of morphological, immunological, and biochemical methods to investigate some of the cell biological properties of the ECM receptors. Specific monoclonal antibodies will be raised against these cell surface ECM binding proteins. These antibodies will enable a detailed evaluation of the distribution, movement, and metabolism of the ECM binding sites on the cell surface of migrating and quiescent epithelia. We will determine what binding proteins are present on migrating and quiescent corneal epithelia and which are required for migration and/or adhesion. The movement of ECM binding proteins will be evaluated by fluorescently labeling the binding sites on living epithelial cells. Finally we will investigate the turnover of the ECM receptors on healing epithelia. This new information will contribute to the understanding of clinical conditions which are characterized by loss of the normal relations between epithelium and matrix of the cornea.